The defending MLS champion Galaxy did not lose a home game all of last season and they seemed on their way to a victory in their season opener when Edson Buddle scored on a header in the 71st minute.
Los Angeles then collapsed down the stretch, beginning when the Galaxy's Sean Franklin put the ball into his own net to create a 1-1 tie.
Salt Lake then pounced on the stunned Galaxy to score twice in 5 minutes.
The Galaxy went 12-0-5 at home last season. Real Salt Lake finished third in the Western Conference behind Los Angeles and Seattle.
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